Welcome to PondBoss. I am no pro on this but I would hazard a guess that the best soils for the core are the width of the equipment being used to compact it. So if your doser is xx' wide.....your core will match that same width.

Doser spreads a lift.....compacted by sheepsfoot and then rinse and repeat.

Have you dug any test holes on site to see if you need to have clay brought in? If you have good soils on site you may not need to bring anything "extra" to the site.

Hopefully somebody else will chime in that has a little more expertise.

1.5acre LMB, YP, BG, RES, GSH, Seasonal Tilapia
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